Dyeing of polycarbonamides of bis(paraamino-cyclohexyl)methane and dodecanediodic acid with anionic dyes

ABSTRACT

WHEREIN R IS THE SAME OR DIFFERENT MEMBER OF THE CLASS CONSISTING OF HYDROGEN AND METHYL WITH SELECTED ANIONIC DYESTUFFS UNDER ACIDIC CONDITIONS AND TEMPERATURES OF BETWEEN ABOUT 180* TO 212* F. BY USE OF SELECTED ORGANIC CARRIERS, THE USE OF PRESSURE IS NOT REQUIRED.   -NH-CO-(CH2)10-CO)-   -(NH-(R-1,4-CYCLOHEXYLENE)-C(-R)2-(R-1,4-CYCLOHEXYLENE)   PROCESSES ARE PROVIDED FOR THE DYEING OF SILK-LIKE LINEAR, HIGH MOLECULAR WEIGHT POLYAMIDE FIBERS CONTTAINING AT LEAST 90% REPEATING UNITS OF THE FOLMULA

Int. Cl. D06p /04 US. Cl. 8-173 6 Claims ABSTRACT OF THE DISCLOSUREProcesses are provided for the dyeing of silk-like linear, highmolecular weight polyamide fibers containing at least 90% repeatingunits of the formula wherein R is the same or different member of theclass consisting of hydrogen and methyl with selected anionic dyestuffsunder acidic conditions and temperatures of between about 180 to 212 F.By use of selected organic carriers, the use of pressure is notrequired.

The present invention relates to processes for dyeing polyamide fiberscontaining at least 90% of the repeating units of the formula wherein Ris the same or different member of the class consisting of hydrogen andmethyl. At least 40% by weight of the diamino constituent of therepeating units is of the trans, trans stereoisomeric configuration.

The manufacture of these fibers as well as the abovediscussed structureis detailed in US. Pat. 3,393,210 to Speck, which specification isincorporated by reference herein. a

As exemplary of these materials is the polyamide polycondensate of 4,4'-diamino-dicyclohexylmethane with dodecanedioic acid. Such material iscommercially avail able from Du Pont in different grades, depending onfinish, denier, etc., as nylon types 472 and 473, as well as Qiana. Thelatter materials have a silk-like handle, a density of 1.04 and acrystallinity similar to that of polyester fibers, as reported in anarticle entitled The Dyeing of Synthetic Polymer Fibers, A. Liddiard,appearing in Review of Progress in Coloration, vol. 1, p. 64, Junel967-September 1969.

US. Pat. No. 3,393,210, mentioned above, further discloses that thepolyamide fibers are dyed under pressure in the presence of carrierscustomarily used for polyester fibers at temperatures between 115 and120 C. This behavior is rather atypical of polyamides since polyamidessuch as nylon 6 or 66 are readily dyed in the absence of carriers. Thisdifficult dyeability is attributed to the relatively few and relativelyinaccessible free amino groups on the fiber. It was, therefore, anobject of the present inventors to achieve dyeings at atmosphericpressure and at temperatures up to about the boiling point of theaqueous dye solution, e.g. about 212 F.

The Liddiard article, discussed above, does disclose that the Du Ponttype 472 polyamides may be dyed with disperse dyes at the boil in thepresence of a carrier, or in the absence of a carrier at even highertemperatures.

; United States Patent 0 Since disperse dyes do not give a verysatisfactory heat sublimation light or wash resistance, it was a furtherobject of the present inventors to find a method for dyeing type 472nylon fibers with traditionally fast classes of dyestuffs.

The above-discussed objectives could not be attained by the use ofconventional polyamide, e.g. nylon-6 or 66 formulations since thesemethods gave little or no dye exhaustion.

The above objectives were finally realized by the use of a carefullycontrolled combination of pH, temperature, dyestuif and carrier.

With respect to carriers, the most preferred is benzophenone, however,this may be employed and mixed with other carriers such as butylbenzoate, especially in a 1:1 mixture. Other operable carriers includebenzyl benzoate, phenyl benzoate, o-bromo benzoic acid, 2-chloro benzoicacid, mono benzyl phthalate, o-anisaldehyde, benzoin, succinic acid andtoluic acid. Such carriers may be employed alone or in admixture witheach other as well as with benzophenone and/or butyl benzoate. Normally,10 to 25 weight percent of carrier, based on the weight of the fiber tobe treated, produces satisfactory results.

With respect to temperatures of dyeing, about 180 F. up to about theboiling point of the aqueous dyebath, e.g., about 212 F., may beemployed with temperatures in the range of 200 to 212 F. beingpreferred.

Control of pH is very important and a pH range of between 2 and 5 mustbe employed to insure substantial dyebath exhaustion. Conventional acidsused in dyebath formulations, e.g., formic, acetic, sulphuric orphosphoric acid are preferably employed. Formic acid is most preferredbecause it offers the highest degree of exhaustion.

With respect to dyestuffs, as stated above, it was a primary object toemploy fast dyes since it was already known that disperse dyes could beemployed. Therefore the dyestuffs falling within the scope of thisinvention are the anionic dyes. Certain anionic dyes were found to bemore satisfactory than others and among these are the direct dyes, e.g.,Direct Red 81 (Cl. 28160), 2:1 premetallized azo dyes, e.g., Acid Red201 (01. 18761) and Acid Red 180 (CL 8736) and azo or anthraquinone aciddyes. Among the azo and anthraquinone acid dyes, the most preferred arethe monosulfonated ones. Similarly, among the 2:1 premetallized dyes,the monosulfonated and monosulfonamides are most preferred.

Dyes such as monosulfonated azo Acid Yellow 29 (CI. 18900),monosulfonated azo Acid Red 4 (CI. 14710) and monosulfonatedanthraquinone Acid Blue 27 (CI. 61530) gave excellent color yield and,in most cases, were totally exhausted after 60 minutes at 212 F. On theother hand, dyes such as Acid Orange 45 (CI. 22195) Acid Red 73 (CI.27290), Acid Blue 113 (CI. 26360) and Direct Yellow 44 (CI. 29000) gavepoorer color yield and were far from total exhaustion. The latter dyesall have more than one acidic groups, i.e. sulfonic or carboxylic acidgroup, however, by use of the carriers and conditions of the presentinvention, even these dyestuffs produced dyeings unattainable by theprior art.

Conventional anionic and nonionic wetting agents may be employed ifdesired. Anionic wetting agents are preferred.

The following specific embodiments are merely exemplary and are notlimiting:

EXAMPLE 1 10 g. of Du Pont type 472 nylon fiber is immersed in a bathprepared as follows:

To 300 cc. water at F. is added 2.0 g. benzophenone (dissolved in asmall amount of ethanol and emulsified with Tween 20) and 0.05 g.Irgalev PBF anionic wetting agent. The pH of the bath is adjusted to 3.0with formic acid and 0.2 g. Erio Fast Blue GRL (Acid Blue 25; CI. 62055)is dissolved.

The fiber is immersed in the dyebath and the dyebath is heated at 2-3F./min. to the boil, i.e., about 212 F. The fiber is boiled for aboutone hour, washed with water and dried to achieve a deep, bright bluelevel dyeing. Fastness to wet and light conditions were outstanding.

EXAMPLE 2 Proceeding substantially in the same manner as in Example 1,several organic chemicals were employed to determine their carriereffect. Several were found to give significant exhaustion and these arebenzyl benzoate, phenyl benzoate, o-bromobenzoic acid, 2-chlorobenzoicacid, monobenzyl phthalate, o-anisaldehyde, benzoin, succinic acid, andtoluic acid.

EXAMPLE 3 Proceeding as in Example 1 but employing 0.2 g. of Acid Yellow29 CI. 18900 and 1.5 g. of a 1:1 by weight mixture of benzophenone-butylbenzoate emulsified with Tween 20 (polyoxyethylene sorbitan monooleate),an excellent bright yellow dyeing was achieved. Acid Red 4 (CI. 14710)and Acid Blue 27 (Cl. 61530) produced similar excellent results with, inmost cases, total exhaustion in 60 minutes at 212 F. When employing dyessuch as Acid Orange 45 (Cl. 22195), Acid Red 73 (CI. 27290), Acid Blue113 (CI. 26360) and Direct Yellow 44 (CL 29000) (all of which containmore than one acidic group, e.g. carboxylic and sulfonic), exhaustionwas decreased.

We claim:

1. A process for the dyeing of linear high molecular weight silk-likepolyamide fibers, wherein recurring polyamide linkages are an integralpart of the polymer chain and at least 90% by weight of the repeatingunits of said polyamide are of the formula:

wherein R is the same or different member of the class consisting ofhydrogen or methyl which comprises immersing said fiber in an aqueousdyebath containing (a) a carrier, benzophenone, in an amount effectiveto produce a level dyeing,

(b) an anionic dyestulf selected from the group consisting of azo andanthraquinone acid dyestuffs, 2:1 premetallized azo dyestuffs and directdyestuffs,

the pH of said dyebath being in the range of 2 to 5 and the temperatureof said dyeing being from about F. to about 212 F.

2. The process according to claim 1 wherein the pH is adjusted tobetween 3 and 5 with formic acid and the dyeing temperature is betweenabout 200 F. and 212 F.

3. The process according to claim 2 wherein the carrier is employed atconcentrations of between 10 and 25% by weight based on the fiber.

4. The process according to claim 3 wherein the acid dyestutf is amonosulfonated azo or monosulfonated anthraquinone.

5. The process according to claim 3 wherein the dyebath contains ananionic or non-ionic wetting agent.

6. The process of claim 1 wherein butyl benzoate is present in additionto the benzophenone.

OTHER REFERENCES Lynn: Advances in Textile Processing, vol. I, 1961,

pp. 360-363, pub. by Textile Book Pub. Inc., New York, N.Y.

DONALD LEVY, Primary Examiner

